Push button operator



1967 c. B. SOHNS ETAL PUSH BUTTON OPERATOR 3 Sheets-Sheet 1 Filed Oct.23, 1965 ATTORNEY.

1967 c. B. SOHNS ETAL 3,305,660

PUSH BUTTON OPERATOR- Filed Oct. 25, 1965 J'ShBeW-Sheet 2 INVENTORfi MMATTQRNEY.

Feb. 21, 1967 Q so -ms ETAL -3,305,660

PUSH BUTTON OPERATOR Filed Oct. 25, 1965 w5 Sheets-Sheet s Z ATTORNEY.

United States Patent Office 3,305,559 Patented Feb. 21, 1967 3,305,660PUSH BUTTON OPERATOR Carl B. Sohns, Milwaukee, and Dom L. Pettit,Wauwatosa, Wis, assignors to Square D Company, Park Ridge, Ill., acorporation of Michigan Filed Oct. 23, 1965, Ser. No. 502,926 11 Claims.(Cl. 200-172) This invention relates to push button operators foroperating push button switches, including push button operators of theunilluminated and illuminated types.

An important feature of the invention resides in the combination of anoperator push button and a supporting base which is adapted forconnection to a panel or the like and which has effective guide bearingsurfaces disposed adjacent the opposite ends of the operator pushbutton, respectively, and particularly at the forward end and near therear end of the base, and in guiding relation to the operator pushbutton for assuring effective guiding of the operator push button.

Specifically the invention relates to a push button operator which is sodesigned that a large number of its parts can be used either in anunilluminated or an illuminated type of push button operator, whereby asmaller inventory of parts is sufiicient for meeting the needs ofcustomers.

Another feature is to provide an operator of the character describedwherein the push button is guided for axial movement at spaced oppositeend portions of the button stem, and an oil seal is provided in a spacein the base between the opposite end portions for assuring sealingaround the stem, the seal being retained effectively in position withoutdanger of pinching, disalignment, and the like.

A very specific object resides in the connection of the operator buttonwithin the base by means of a snap-in nylon retainer in snap fasteningengagement with the stern of the operator push button.

Another specific object is to provide the operator button with a hollowstem which is adapted to accommodate a light for the illumination ofthehead of the push button.

Various other objects and advantages will become apparent from thefollowing description wherein reference is made to the drawings, inwhich:

FIG. 1 is an exploded view of the parts of an unilluminated type of pushbutton operator embodying the invention, the parts being arranged inaxial alignment, portions thereof being shown in section for clearnessin illustration;

FIG. 2 is a top plan view showing the parts illustrated in'FIG. 1 intheir assembled relation;

FIG. 3 is a front elevation of the structure illustrated in FIG. 2, apart thereof being shown in section, as indicated by the line 3-3 inFIG. 2;

FIG. 4 is a view similar to FIG. 3 showing an illuminated operatorwherein the lens is guarded so as to be visible substantially only fromthe front of the operator; and

FIG. 5 is a view similar to FIG. 3 showing an illuminated operatorembodying the principles of the present invention.

Referring first to FIGS. 1 through 3, the operator comprises a base,indicated generally at 1, in the form of an open end sleeve having aradially extending flange 2 at one end. The flange 2 is provided with aplurality of tapped bores which are adapted to receive screws forsecuring the base and the body of a push button switch S together. Thebase 1 has an axial passage formed by an internal annular guide wall 4at the forward end of the base and adapted to surround and guide thehead of a push button of the operator for endwise sliding movementaxially of the passage, as will later be described. Between the ends ofthe passage, the sleeve is provided with an internal annular rib 5having a stop shoulder 6 facing rearwardly of the sleeve passage of thesleeve. The rib has an annular internal guide wall 7 of smaller diameterthan the guide wall 4 and which is adapted to engage and guide the stemof the operator push button, as will later be described. The rib 5 isalso provided with a forwardly facing radial shoulder 8 extending fromthe forward edge of the wall 7 radially outward a short distance to awall portion 9 which is spaced radially outwardly from the wall 7. Theshoulder 8, wall 9 and push button stem provide an annular space foraccommodating an oil seal.

The push button of the operator comprises a head 12, having an externalrearwardly extending annular flange 13 which extends from the forwardface of the head 12 rearwarclly, part way toward the opposite end of thepush button. The push button also has a hollow cylindrical stem 14 inthe form of a cylindrical shell, less diameter than the flange 13 andcoaxial therewith.

The outer peripheral surface of the flange 13 engages and is guided foraxial movement by the guide wall 4 of the base while the externalperipheral surface of the stem 14 engages and is guided by the guidewall 7.

The flange 13 is spaced radially outwardly from the stem 14- so as toprovide an annular channel 16 in which one end of a coil return spring17 is disposed so that its one end engages the inner face of the head 12and urges the push button forwardly. An annular spring support 18 isjuxtaposed against the shoulder 10 of the rib 5. It is engaged by theopposite end of the spring 17 and it is held firmly in face to facejuxtaposition with the shoulder 10 thereby.

The annular support 18 extends radially inwardly beyond the shoulder 10and overhangs the shoulder 8 in axially spaced relation. The support 18fits the stem 14 with operating clearance, thus providing a forwardlyfacing channel in which is disposed an oil seal 19 which provides aneffective seal between the radial wall 9 and the adjacent externalperipheral wall of the stem 14.

In order to limitthe forward movement of the stem relative to the base,a retainer '20 is connected to the inner end of the stem. The retainer20 is aligned with the stop shoulder 6 and arranged to engage thatshoulder and to constrain the operator push button from undue movementforwardly, thus assuring proper guiding relation with the walls 4 and 7at all times.

The retainer 2G is shown as annular. At its forward end, it has aninternal annular bead or shoulder 21 extending radialiy inwardly fromits inner periphery and terminating axially in spaced relation to therear end of the retainer. The rear end of the stem 14 is provided with aradially open annular groove 22 and a tapered guiding nose portion 23 atits rear end. The stem 14 has two axially extending notches 24 extendingthrough its peripheral wall. The retainer 20 is provided with radiallyextending tongues 25 which are receivable in the notches 24 withcircumferential clearance. The notches impart a certain flexibility tothe extreme rear end of the stem 14. The stem and the retainer are madeof relatively stiff, but slightly resilient, self-restoring material.The stem and retainer can be assembled by pressing the retainer forwardend foremost over the tapered guiding nose portion 23 of the stem, thuscontracting the rear end of the stem radially and expanding the retaineruntil the rib 21 passes into alignment, radially of the stem, with thegroove 22. Thereupon the retainer 20 and the stem 14 approach fullyrestored condition, seating the rib 21 firmly in the groove. The tongues25 fit the notches 24 with very limited circumferential clearance whenthe stem is uncontracted. Hence, when the retainer is snapped intoplace, the notches in the rear end of the stem 14 firmly engage thetongues and assure that, when the retainer 20 is self-restored to itsoriginal condition, it is constrained from rotation relative to the stem14 and also limits the forward movement of the push button by the spring17.

The retainer may be made of nylon, a synthetic plastic well known in theplastic art.

The base 1 is externally threaded, as indicated at 26, at its forwardend for receiving an internally threaded ring nut 27. The base canreadily be inserted through a hole in the panel when the nut 27 isremoved, and oil seal washers 28 may be disposed between the rear faceof the panel P and a shoulder on the base 1.

If desired, a colored indicating disk 29 may be snapfitted into asuitable cavity in the forward end of the push button head 12, and ametal or plastic thimble 30 may be press fitted in the interior of thestem 14.

In some cases it is desirable to have the front face of the push buttonforwardly from the forward end of the nut 27, as in the form illustratedin FIG. 3. On the other hand, sometimes it is desirable to have theforward face of the head flush with the forward end of the nut, in whichcase a nut 2701, as indicated by the dot and dash lines in FIG. 3 may beprovided, this nut being the same in all respects as the nut 27 exceptfor a greater length axially. Again, it is sometimes desirable that theforward face of the push button head 12 be rearwardly from the forwardend of the nut, in which case a nut 27b may be provided, this nut beingsufficiently long so that while it is seated and holding the base firmlyin position on a panel, its forward end is forwardly from the forwardface of the push button 12.

Referring next to FIG. 4, a similar structure is illustrated. It employsa base 31 similar to the base 1. The base 31 has an internal annularguide wall 32 at its forward end, and an internal annular wall 33 nearits rear end. An operator push button 34 is provided and, as illustratedin FIG. 4, is essentially the same as the push button heretoforedescribed, except that its axial passage 35 extends entirely through thepush button and is open at both ends. The push button 34 has an externalannular flange 36 guided by the wall 32, and the external surface of thestem is guided by the wall 33. The base 31 is provided with externalthreads 37 on which is threaded a ring nut 38 for fastening the base andthe parts carried thereby to a panel. The push button head is providedwith external threads 39 for cooperation of internal threads of aconcavo-convex lens 41, disposed with its convex face forwardly inalignment the passage 35, thus providing connecting means detachablyconnecting the lens to the head.

A suitable annular guard 42 is externally threaded for engagement withinternal threads 43 at the forward end of the ring nut 38. The guard hasan annular portion 42a which extends forwardly from the threaded portioninto surrounding relation to the side walls of the lens 41, thusblocking the passage of light laterally of the lens. A suitable electricbulb 45, with the usual fittings and socket, may be mounted in thepassage 35 for providing the desired illumination.

In some cases it is desirable to have the lens unshielded from the side,in which case the structure illustrated at FIG. 5 may be used. In thisstructure, a ring nut 47 is substituted for the ring nut 38, and isprovided with an internal annular shoulder 48 which is disposed insurrounding relationship to the rear end of a lens 49. No guard, such asthe guard 42, is provided, thus leaving the lens unshielded laterally.

In all forms of the invention it may be desirable to constrain theoperator push but-ton from rotation about its axis. This is particularlytrue in the case of illuminated push buttons so as to prevent rotationof the push button by the lens when the lens, such as the lens 41 inFIG. 4 or lens 49 in FIG. 5, are being unscrewed to replace the bulb,and by the bulb when it is rotated for connection and disconnection.

For this purpose, the base 1 is provided with an internal rib 59 whichextends endwise of the base. The retainer 2%) is provided with fingers51 which engage circumferentially opposite sides of the rib 50 withoperating clearance, and cooperate therewith to constrain the stem 14from rotation about its axis relative to the base 1.

It is apparent that with the structure described, with merely asubstitution of different ring nuts, an unilluminated push buttonoperator can be provided in which the button is normally exposedforwardly and laterally, or is exposed forwardly only with its forwardface flush with the operator, or is exposed with its forward facedisposed rearwardly from the forward end of the operator.

Again, by substituting a modified form of ring nut and a different typeof push button, an operator can be provided which is readily adaptablefor illumination, the other parts remaining the same as for theunilluminated operator. In the latter case, the substituted push buttonhas a head which accommodates a lens detachably, and the new ring nutcarries a guard such that the lens is exposed only forwardly.Substitution of still another ring nut permits the omission of the guardso that the lens is exposed laterally also as well as forwardly.

In all cases, the push button is well guided near the forward end of thebase and near the rear of the base, and is non-rotatively accommodatedin the base. The oil seal is disposed therebetween. The retainer springsand other portions and the base may be the same in all instances.

Having thus described our invention, we claim:

1. A push button operator comprising a base having a forward end and arear end, and having a passage extending forwardly and rearwardlytherethrough, said base having a forward internal annular guidewall atthe forward end of the passage and coaxial therewith, and having arearward internal annular guidewall coaxial with, and spaced axiallyrearwardly from, the forward guidewall, a push button comprising a headand a stem, said head disposed in said passage and guided at its outerperiphery by said forward guidewall for movement axially forwardly andrearwardly of the passage, said stem having an external peripheral walldisposed in said passage and guided by said rearward guidewall formovement axially forwardly and rearwardly, said base having an internalstop shoulder in said passage disposed rearwardly from said rearguidewall and facing rearwardly of the passage, and retainer means onthe stem rearwardly from said shoulder and aligned therewith in positionto engage the shoulder and limit the forward movement of the pushbutton, thereby constraining said head and stem from moving forwardlyout of guided relation to said forward and rearward guidewalls,respectively.

2. A structure according to claim 1 wherein an internal annular rib isdisposed in the passage of the base and extends radially inwardly intothe passage, and the rear guidewall is on the inner periphery of therib, and said stop shoulder is on the rear of the rib.

3. A structure according to claim 2 wherein said rib has a forwardlyfacing annular shoulder of greater outer diameter than the rearguidewall, an annular spring support is juxtaposed on the forwardlyfacing shoulder in surrounding relation to the stem, a spring isinterposed between the head and said spring support, and said rib has anauxiliary forwardly facing shoulder disposed between the forwardshoulder and the stop shoulder and of greater outer diameter than therear guidewall and of lesser diameter than the forwardly facingshoulder, whereby a channel is provided in surrounding relation to thestem between the forwardly facing shoulders, and an oil seal is disposedin the channel and is in sealing relation with said stem and with aninwardly facing annular wall of the rib.

4. A structure according to claim 3 wherein the push button head has arearwardly extending peripheral flange of larger diameter than the stem,and the spring at its forward end engages the rear face of the headportion between the flange and the stem portion.

5. A structure according to claim 2 wherein the retainer means is anannular member, and complementary snap-fastening means are provided onthe inner end of the stem and on the member for securing the member infixed position axially of the stem.

6. A structure according to claim 5 wherein the rear end portion of thestem is relatively stiff, resilient and contractible radially andself-rest0ring, said member is relatively still and resilient andexpansible radially and selfrestoring, a complementary snap-fasteningmeans include interfitting annular means on the rear end portion of thestem and on the member.

7. A structure according to claim 6 wherein the mem' her is composed ofNYLON.

8. A structure according to claim 1 wherein said stem is hollow.

9. A structure according to claim 1 wherein the push button stem ishollow in the form of a cylindrical sleeve which is open at both ends,the head has a passage extending entirely therethrough axially of thestem and joining the forward end of the passage in the stem, aconcave-convex lens is disposed on the head with its con'vex faceforward, and said lens extends forwardly from, and is in alignment with,said passage in the head; and connecting means. detachably connect thelens to the head.

10. A structure according to claim 9 wherein a ring nut and an annularguard are provided, said ring nut is in threaded engagement with thebase; and the annular guard is detachably supported by the ring nut inradially spaced relation to, and in surrounding relation to, the lens.

11. A structure according to claim 1 wherein oil-sealing means aredisposed in the passage forwardly from, but close to, said stopshoulder.

No references cited.

ROBERT K. SCHAEFER, Primary Examiner.

H. O. JONES, Assistant Examiner.

1. A PUSH BUTTON OPERATOR COMPRISING A BASE HAVING A FORWARD END AND AREAR END, AND HAVING A PASSAGE EXTENDING FORWARDLY AND REARWARDLYTHERETHROUGH, SAID BASE HAVING A FORWARD INTERNAL ANNULAR GUIDEWALL ATTHE FORWARD END OF THE PASSAGE AND COAXIAL THEREWITH, AND HAVING AREARWARD INTERNAL ANNULAR GUIDEWALL COAXIAL WITH, AND SPACED AXIALLYREARWARDLY FROM, THE FORWARD GUIDEWALL, A PUSH BUTTON COMPRISING A HEADAND A STEM, SAID HEAD DISPOSED IN SAID PASSAGE AND GUIDED AT ITS OUTERPERIPHERY BY SAID FORWARD GUIDEWALL FOR MOVEMENT AXIALLY FORWARDLY ANDREARWARDLY OF THE PASSAGE, SAID STEM HAVING AN EXTERNAL PERIPHERAL WALLDISPOSED IN SAID PASSAGE AND GUIDED BY SAID REARWARD GUIDEWALL FORMOVEMENT AXIALLY FORWARDLY AND REARWARDLY, SAID BASE HAVING AN INTERNALSTOP SHOULDER IN SAID PASSAGE DISPOSED REARWARDLY FROM SAID REARGUIDEWALL AND FACING REARWARDLY OF THE PASSAGE, AND RETAINER MEANS ONTHE STEM REARWARDLY FROM